


Fate/Last Crusade

by White Trenchcoat (white_trenchcoat)



Category: Fate/Zero, Fate/kaleid liner PRISMA ILLYA, Fate/stay night & Related Fandoms
Genre: F/M, Features Fate/Zero characters, Kiritsugu says screw you to the Holy Grail Wars, Prequel, before the series starts, but set in the world of Fate/kaleid, canon-ish?, it doesn't end well for Kayneth
Language: English
Status: In-Progress
Published: 2018-02-23
Updated: 2018-03-12
Packaged: 2019-03-22 03:30:14
Rating: General Audiences
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 2
Words: 3,066
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13755372
Author URL: https://archiveofourown.org/users/white_trenchcoat/pseuds/White%20Trenchcoat
Summary: Receiving a vision of the future from his alternate version of himself, Kiritsugu sets out to stop the Fourth Holy Grail War and prevent any more from occurring. If he fails, his wife and daughter are doomed to a dark and depressing future.





	1. The Beginning of the End

**Author's Note:**

> So yeah I read on the Wiki that Fate/Kaleid Linear Prisma Illya is only that way because Kiritsugu stopped the Fourth Holy Grail War before it started. So this is how I think it would have gone. Hence, canon-ish because it is suggested in the series, but not outright stated.
> 
> Enjoy, it's not a long work but I think it will be fun.

Snow fell thickly, framing the scene better than any photographer could. A dusting of white already covered the shoulders and head of Kiritsugu Emiya as he bent down to kiss his tiny daughter. She giggled, tugging at a lock of his hair before he handed her over to his wife. Irisviel Von Einzbern smiled as she took their child in her arms, kissing her on the forehead. "Say bye bye, Ilya. Daddy will be back soon" she whispered, moving away and caressing the soft, white hair.

He turned to look at the car's driver, stoic and unmoving as always. He'd given her his instructions earlier that day, and nothing else needed to be said. When it was done… maybe, but for now, she was still his 'work associate'. Seeing the three women together, he found it funny how they were the only people he really cared about in the world. "I will call you when it's over." He closed the door, putting his collar up against the biting wind.

"Be safe" asked Irisviel, reaching out a hand to grasp Kiritsugu's. Illyasviel Von Einzbern's father nodded, stepping back as the engine started up. A sad smile was the last expression he saw on her face before Maiya drove them away through the snow.

Illya's last image, if he didn't make it, would be her father's smiling face in the snow; he couldn't have wished for better. Now they were hidden somewhere even he didn't know, Kiritsugu Emiya shut off any emotions he might have had. His face transformed into one as cold as the wind that fought against his skin.

***  
It came again; the fire and the dying. Soon he'd see the burning cottages, the screaming islanders, and the cheerful face of a doomed girl. The dreams-turned-memories of the dying and the damned were nothing new to him. Seeing an entire village purged, the cursed survivors brutally murdered by black clad mages, would have messed up any kid. Sometimes he was either so exhausted, or guilt ridden, that fresher memories overrode the old.

Kiritsugu was used to it, and could predict everything he was about to see. So when he saw glass and steel instead, the pavement below him concrete instead of sand, he was surprised. It was worse than before; no, it was an entirely new vision of the apocalypse. A great chunk of this unknown city lay in ruins, the inferno around him reaching high enough to touch the clouds. An older Kiritsugu wandered through it towards him, a broken man struggling to survive.

Kiritsugu stepped back from his future self as it walked past, limping slightly. Before he could see more, a dark, murky liquid rose up over the image to blacken it.

"Illya."

***  
Kiritsugu opened his eyes, looking into the canopy of his bed above. Sitting up, hands trembling, he was dying for a cigarette but knew Irisviel didn't approve of the ashes in the sheets. Instead, he took comfort from her sleeping form, pale hair stirring warm feelings in his heart. Unable to sit or lie still, Kiritsugu slowly moved to the edge of the bed and sat up, breathing slowly. Thankful for the electric heating that warmed this warm, and the rest of the mansion, the dark haired man look out of the snow covered window.

A drawn and tired man stared back from his reflection. In that moment, he remembered the dream again, and let out a deep groan at the images that stuck out amongst the rest. His head felt full, as if someone had taken the memories of someone else and rammed them into his mind. Rapid and confusing, he nonetheless sorted and filed them away, gaining the bigger picture from the small flashes.

It was unbelievable; a Fifth Holy Grail War. His entire goal of winning the Grail was to stop any more violence or conflict from occurring; yet the fact was there. Even more damning; he had won the grail and nothing had changed. Even with the couple accepting Irisviel's fate, he couldn't, and knew she wouldn't, be able to accept their Illya's.

He thought hard, trusting himself wholeheartedly. He knew his own face, and the expression on his other self was not one of disappointment or failure, or even deceit, but disillusionment. He had won, and chosen instead to reject it.

Rationally, he dismissed time travel as the pure fantasy it was. An alternate timeline, however, where everything had moved quicker with a different future, could be likely. However, that just raised more questions, since if he had had the ability to pass information like that, why wouldn't he give himself some advantage? A warning or prophecy would have been helpful; unless he could only choose certain things.

The cold hand on his shoulder made him jump, snapping him out of the reverie. He turned, staring madly at the gentle eyes and bemused face of his wife. Her smile faltered a little at his expression, then firmed. "Is everything all right, Kiritsugu?" asked Irisviel Von Einzbern, white hair framing a face carved by angels.

No, it wasn't all right, he thought, feeling the tears fall. He'd just learnt everything they had planned for would be moot. Their daughter… oh god, it was Shirley all over again, an innocent girl doomed because of him. Instead of a bright future, she would be forsaken and abandoned, her only father a huge, grotesque servant.

Iris hugged him from behind, and Kiritsugu let out a deep sigh at his wife's gentle touch. Her scent, so unique to her, free of perfume or musk, extinguished any tumulus thoughts he might have had. He turned and embraced her properly, imagining the adorable look of bemusement on her face.

***  
Irisviel

"So our little Illya is doomed, no matter what happens." She looked in the direction of their daughter's room, thinking about the future Kiritsugu had revealed to her. "You really believe it?"

"I trust him, that is, me. If I really thought that future was better, I would have used this second chance to tell me everything I needed to succeed. Instead, he didn't tell me how to win, but to instead stop it completely. The look in his eyes… it haunts me."

It was true. Kiritsugu had always kept his goal in mind. She didn't know all the details of his life, future plans included, but knew at least that he would do anything to win. Her husband had sabotaged himself, and whether it came from some guilt complex or a future version, it did warrant careful thought.

"Whichever Kiritsugu it is, I believe in them. If you want to take it as truth, then I will do the same." It was easy to say, for she would go to the ends of the earth for him; the first person to show her compassion. "But, what can we do? Father won't give up, and the elders will force us to take part. Without the Einzbern's, there can be no vessel for the Grail, and the other Magus families will come after us if the family doesn't. They want the grail, even if we don't."

Deep in the back of her mind, she felt the dark thought that nested there. Even if she was just a homunculus, she felt some semblance of love for her father and creator. Kiritsugu enclosed his hand over hers, and staring into his sad eyes, saw he had come to the same conclusion.

It would damn them, and the world might even reject them for doing it. "How much do you love Illya?" he asked, and any lingering doubts fled from her mind. Illya, or the family? It was simple and clear, with only one choice.

"More than anything. She's so beautiful she feels me with hope. To just see her smile makes me think it's all been worth it" replied the mother honestly, understanding that if they were damned, Illyasviel would be saved.

What parent wouldn't accept that?

***

Kiritsugu Emiya stood patiently in the middle of the grand hallway. A high ceiling depicted elegant, Rennaisance art, portraits of stern looking men and women looking disapprovingly at the mercenary. At the top of the grand staircase, a large portrait depicted the brown hair and red suit of his next target. A door opened somewhere, and the painting's subject now walked down the stairs. A glass of crimson wine moved to and fro gently in his hands, the eternally smug look removing any sense of guilt from Kiritsugu's mind.

"Kiritsugu Emiya-kun, The Magus killer. Well well well, what a surprise to see you here. I take it you want some reward for killing the Einzberns?" Despite the casual air of his words, his free hand was clenched into a fist, telling Kiritsugu all he needed to know. Still, he could play along with the arrogant mage.

"What if I did?" replied Kiritsugu, using the conversation to take in the room. The door behind him was closed, with four doors leading off from the room that were open to him. Two above, two below, with sigils on the walls he could glimpse.

Tokiomi chuckled, shaking his head in admonishment. He took a sip from his glass, locking eyes with the mercenary. "You would be disappointed, as while we are grateful for your assistant, we still need a vessel for the Holy Grail. If you have killled the hosts, then it cannot take place."

"That is good to here, since I'm not here for a reward." Moving at triple his speed, the gun came up and fired in one smooth movement. Any mage hit with this bullet would find themselves writhing in agony on the floor, their magic circuits cut and reconnected in the wrong configuration.

His target made no attempt to move, or even put up a shield, as a long, katana-like blade blocked the bullet's path. A figure in black jumped from the upper landing, five identical blades brought down to slice Kiritsugu to ribbons. He jumped back, the carpet beneath their feet shredded.

"I'm sure you know Kotomine-san? He's a good friend of the family, and has a stake in the Holy Grail War himself."

"As do I" proclaimed a haughty voice, a third person joining the assembled defenders. Kiritsugu narrowed his eyes, taking in the blue robes and blonde hair of Kayneth El-Melloi the II. Three of the potential masters also meant triple the threat. The mercenary didn't have to pretend to be worried at the force before him. "The Holy Grail War must continue; anything else is unacceptable."

"Run now; you might escape" added the Tohsaka Family Head, finishing his wine and placing it on the stair's banister. Each Master took a different side, facing their newly discovered nemesis.

Kiritsugu shook his head, readying his automatic weapon.

"There will be no more Holy Grail Wars."


	2. Chapter 2: Escalation

**Summary for the Chapter:**

> It's Kiritsugu vs Tokiomi and Kotomine; who will come out on top? Guest starring Kayneth.

They were readying strategies to repel an attack, so Kiritsugu had to provoke a reaction. An arcing spray of bullets headed for the three mages in front of him, the mercenary sidestepping quickly for any counter attacks.

True enough, Tokiomi conjured up a magic circle that stopped the bullets and sent a fireball at the Magus, Kirei Kotomine deflected and cut the projectiles to pieces with his Black Keys, stepping in front of the Tohsaka family head. A wall of mercury surrounded Kayneth, and he knew then the Magus had made made a mistake in revealing his weakness so soon.

In an instant, he had switched in his Origin rounds, firing another spread to distract the other two. Unstoppable, the container of powdered ribs struck the silver Code Cast. Magic circuits lit up for a moment before the mercury collapsed in a useless heap of molten metal.

Kayneth screamed as he was revealed, limbs contorted terribly with his back arched in pain, everyong seeing his visceral agony. The other Masters leapt apart, unsure of what was happening as blue lines ran up Kayneth's body and then faded, switched off like lights. Spitting up a torrent of blood, the future El-Melloi Master fell forwards with a weak groan. Tongue hanging out, limbs at awkward angles, he was nothing more than a cripple.

Kiritsugu didn't have time to savour the victory, still aware of the remaining mages who would not be taken down so easily. They knew what he could do, and wouldn't be underestimating him.

Time to run, then, thought Kiritsugu, disappearing through the left hand door. "I'll leave him to you, Kotomine" announced Tokiomi, picking up his wine and walking up the stairs. Kirei simply nodded, chasing after the Magus Killer.

Both had already forgotten about the fallen Master beside them.

<>

Kirei Kotomine felt something unfamiliar inside, watching Emiya dodge and dive through the sigils, their traps activating seconds later. Slashing the walls and floors as he passed erased the gouts of fire and lightning that threatened to damage the priest.

This was fun.

He had no idea how Kiritsugu was moving so fast, or why he was starting to like this game, but knew it would be a good fight. Kirei leapt over the last trap, having seen Kiritsugu bypass it completely, and used his arms to stop the hail of bullets. When they stopped, he hurled all six of his blades down to impale the mage. Two hit the floor, and he yelled an incantation, electricity launching forwards to join the Black Keys hurtling above.

Holy weapons, the claws were a staple of the church's hidden sector, with the training brutally disciplined. He grinned as Kiritsugu was hurled back through the remaining traps, slamming into the wall at the end of the corridor. Landing with a push, he charged down the hallway, picking up the swords as he did.

Of the remaining blades, one was shot out of the air, then another, but Kirei was getting closer. His two remaining Keys pointed up to skewer the intruder. The third, then the fourth, and Kirei's blades were a foot away from the finishing blow.

Lightning fast, the Magus Killer batted his hand away and uppercutted the priest's jaw. Feeling his head rattle, Kirei kicked out wildly, connecting with Kiritsugu's waist. Instinctively, he threw the two Keys in his hand, recovering just in time to see his opponent pinned to the wall.

The two figures watched each other, panting heavily. Kotomine wiped the blood from his mouth, too dazed for the moment to finish him off. "It's nothing personal; but I am employed by Tokiomi to protect him. You cannot win, Kiritsugu Emiya."

"Maybe, maybe not. It's certainly harder than I expected. Kayneth's end made me sloppy, but it's just you and me now that Tohsaka has run away."

"I couldn't be happier for Kayneth's end; we expected nothing less. With you out of the way, the last obstacle will be clear."

"Keep telling yourself that" came Kiritsugu's reply, the Magus Killer suddenly gripping the Black Keys with his hands before Kirei could react.They slashed down in a cross shape at their user who jumped back. Picking up two from the floor, metal hit metal as they connected blades.

Dropping one, Kiritsugu switched in the pistol used on Kayneth ,but the priest avoided his shot, even though it meant ducking and leaving himself open. True enough, a blade sliced up his arm, but his own returned in kind, leaving a diagonal cut across Kiritsugu's face. The Magus swore, dropping the remaining Key and grabbing Kirei by the head to throw him into the wall opposite. He continued around the corner, the priest glowering.

He could imagine Tokiomi laughing as he watched, and became incensed at the situation. Gathering up the remaining Black Keys, he charged after the disappearing black trench coat, trying to figure out where he went.

A flash of black hair to the left, and he charged down the hallway, determined to finish him off once and for all.

<>

Fuck. Those things hurt like a bitch, thought Kiritsugu, turning corners and calling up the blueprints he had memorised before coming in. Setting up delays in those traps had been effective, but Kotomine had been relentless. Nothing less expected from an enforcer of the church.

Still, Tokiomi would be feeling pretty good with himself, and would never imagine Kirei was now chasing a disguised Maiya instead. As he expected, cameras were few and far between, only a modicum of stealth required as he headed for the mansion's centre.

A lifetime of chasing Mages and magical beasts meant he was well-attuned to large areas of magic. Any repository of magical items, scrolls or texts was like a beacon if not properly shielded. Outside the mansion, he had felt nothing, but inside? Like a slight buzzing in his ears.

One room was present in the mansion, but not in the original blueprints, according to the maid who had told him everything. A few drinks, his masculine charms, and she gave him everything. Of course, he'd knocked her out before anything had actually happened, but it still made him feel a bit guilty about Irisviel.

Bingo. The door in front of him crawled and seeped with magical symbols of the highest order. He didn't even recognise most of them, nor the configuration they were in, and whistled despite himself. His facial muscles twinged from the cut that had just now begun to heal, and Kiritsugu frowned. Seeking a way to enter, the glowing golden lock appealed to him immensely, except it had nothing you put a key into.

An incantation? He'd be here forever if he tried that. Before, there had been one method which worked, and he wondered. Taking out the pistol with his unique bullets inside, the Magus Killer wrapped a thick cloth around the gun's barrel to muffle the bang, pointed it at the lock, and fired.

The door shuddered as the sigils died, opening without effort. He kicked it open the rest of the way, prepared for any countermeasures or inhabitants of the room.

Expecting an adult, he missed the lithe, brown haired girl until she passed him, disappearing around the corner before he could grab her. Shit, he thought, tapping the earpiece he wore. "Maiya, a girl saw me. I think it was Rin Tohsaka; they'll probably know you're a fake, so lead them outside."

"Got it" came back the monotonous voice. Kiritsugu had to be satisfied with that, and walked down into Tokiomi's inner sanctum.


End file.
